1. Field of the Invention
The present invention relates to color filters, and more particularly to color filters for reflection or semi-transmission liquid crystal display devices.
2. Background Art
In recent years, attention has been drawn to color liquid crystal display devices as flat displays. Color liquid crystal display devices may be classified into reflection type and transmission type. Reflection color liquid crystal display devices have the following structure. For example, a color filter comprising a colored layer of a plurality of colors (in general, the three primary colors of red (R), green (G), and blue (B)) (and optionally a black matrix and a flattening layer) and a transparent conductive layer is provided so as to face a TFT array substrate having a reflective electrode layer made of a metal, such as aluminum, and a thin film transistor (TFT element), while leaving a predetermined gap between the color filter and the TFT array substrate, and a liquid crystal layer is provided within the gap. A phase difference plate, a polarizing plate, and a front scattering plate are provided on the color filter (in its viewer side). The front scattering plate has the function of scattering light, and is provided for properly scattering light incident on the reflection liquid crystal display device to ensure satisfactory visibility.
Due to the presence of the front scattering plate, however, the conventional reflection color liquid crystal display devices unfavorably suffer from problems of lowered luminance and lowered color properties. This is attributable to the coloring of the front scattering plate. The presence of the front scattering plate poses an additional problem of a parallax (unsharp image). The lowered luminance is unavoidable in the conventional reflection color liquid crystal display devices wherein the front scattering plate is provided on the color filter (in its viewer side). On the other hand, the lowered color properties can be prevented by performing the correction of color properties on a level corresponding to the coloring of the front scattering plate in the color filter. When the color filter is produced by a process which is different from the production process of the liquid crystal display device, however, it is not easy to properly correct color properties of the color filter.
The present invention has been made under the above circumstances, and it is an object of the present invention to provide a color filter which can realize reflection or semi-transmission color liquid crystal display devices having high luminance and excellent color properties.
In order to attain the above object, according to one aspect of the present invention, there is provided a color filter comprising at least a substrate and a colored layer of a plurality of color patterns, said color filter including light scattering fine particles and having a haze of 10 to 90.
In the color filter according to a first embodiment as a preferred embodiment of the present invention, the substrate is transparent, and the color filter further comprises a transparent electrode layer stacked on the colored layer in its surface remote from the substrate, the light scattering fine particles being included as a light scattering layer between the transparent substrate and the colored layer.
In the color filter according to a second embodiment as a preferred embodiment of the present invention, the substrate is transparent, and the color filter further comprises a transparent electrode layer stacked on the colored layer in its surface remote from the substrate, the light scattering fine particles being contained in the colored layer.
In the color filter according to a third embodiment as a preferred embodiment of the present invention, the substrate is transparent, and the color filter further comprises a flattening layer stacked on the colored layer in its surface remote from the substrate and a transparent electrode layer stacked on the flattening layer in its surface remote from the colored layer, the light scattering fine particles being contained in the flattening layer.
In the color filter according to a fourth embodiment as a preferred embodiment of the present invention, a laminate of a driving element layer and a reflective electrode layer is additionally provided between the substrate and the colored layer in such a manner that the driving element layer is stacked on the substrate and the reflective electrode layer is stacked on the driving element layer, the light scattering fine particles being included as a light scattering layer between the reflective electrode layer and the colored layer.
In the color filter according to a fifth embodiment as a preferred embodiment of the present invention, a laminate of a driving element layer and a reflective electrode layer is additionally provided between the substrate and the colored layer in such a manner that the driving element layer is stacked on the substrate and the reflective electrode layer is stacked on the driving element layer, the light scattering fine particles being contained in the colored layer.
In the color filter according to a sixth embodiment as a preferred embodiment of the present invention, the color filter further comprises a flattening layer stacked on the colored layer in its surface remote from the substrate, and a laminate of a driving element layer and a reflective electrode layer is additionally provided between the substrate and the colored layer in such a manner that the driving element layer is stacked on the substrate and the reflective electrode layer is stacked on the driving element layer, the light scattering fine particles being contained in the flattening layer.
In the color filter according to a seventh embodiment as a preferred embodiment of the present invention, the substrate is transparent, and the color filter further comprises a transparent electrode layer stacked on the colored layer in its surface remote from the substrate, the light scattering fine particles being included as a light scattering layer between the transparent substrate and the colored layer and being further contained in at least one of the color patterns.
In the color filter according to an eighth embodiment as a preferred embodiment of the present invention, the substrate is transparent, and the color filter further comprises a flattening layer stacked on the colored layer in its surface remote from the substrate and a transparent electrode layer stacked on the flattening layer in its surface remote from the colored layer, the light scattering fine particles being contained in the flattening layer and at least one of the color patterns.
In the color filter according to a ninth embodiment as a preferred embodiment of the present invention, the substrate is transparent, and the color filter further comprises a flattening layer stacked on the colored layer in its surface remote from the substrate and a transparent electrode layer stacked on the flattening layer in its surface remote from the colored layer, the light scattering fine particles being included as a light scattering layer between the transparent substrate and the colored layer and being further contained in the flattening layer.
In the color filter according to a tenth embodiment as a preferred embodiment of the present invention, a laminate of a driving element layer and a reflective electrode layer is additionally provided between the substrate and the colored layer in such a manner that the driving element layer is stacked on the substrate and the reflective electrode layer is stacked on the driving element layer, the light scattering fine particles being included as a light scattering layer between the reflective electrode layer and the colored layer and being further contained in at least one of the colored patterns.
In the color filter according to an eleventh embodiment as a preferred embodiment of the present invention, the color filter further comprises a flattening layer stacked on the colored layer in its surface remote from the substrate, and a laminate of a driving element layer and a reflective electrode layer is additionally provided between the substrate and the colored layer in such a manner that the driving element layer is stacked on the substrate and the reflective electrode layer is stacked on the driving element layer, the light scattering fine particles being contained in the flattening layer and, in addition, in at least one of the color patterns.
In the color filter according to a twelfth embodiment as a preferred embodiment of the present invention, the color filter further comprises a flattening layer stacked on the colored layer in its surface remote from the substrate, and a laminate of a driving element layer and a reflective electrode layer is additionally provided between the substrate and the colored layer in such a manner that the driving element layer is stacked on the substrate and the reflective electrode layer is stacked on the driving element layer, the light scattering fine particles being included as a light scattering layer between the reflective electrode layer and the colored layer and being further contained in the flattening layer.
According to another aspect of the present invention, there is provided a liquid crystal display device comprising: the color filter according to any one of the first to third embodiments; an electrode substrate comprising a transparent substrate and, stacked on the transparent substrate in the following order, a driving element layer, a reflective electrode layer, and a transparent electrode layer, light scattering fine particles being included as a light scattering layer between the reflective electrode layer and the transparent electrode layer; and a liquid crystal layer sandwiched between the color filter and the electrode substrate.
According to still another aspect of the present invention, there is provided a liquid crystal display device comprising: the color filter according to any one of the fourth to sixth embodiments; a display-side substrate comprising a transparent electrode layer stacked on a transparent substrate, light scattering fine particles being included as a light scattering layer between the transparent substrate and the transparent electrode layer; and a liquid crystal layer sandwiched between the color filter and the display-side substrate.
According to a further aspect of the present invention, there is provided a color filter comprising at least a substrate and a colored layer of a plurality of color patterns, said color filter including light scattering fine particles and a colorant for correction of color properties.
According to the present invention, the inclusion of the light scattering fine particles within the color filter can impart a light scattering function to the color filter per se. This can eliminate the need to provide a front scattering plate on the color filter (in its viewer side). Further, a deterioration in color properties caused by light scattering can be surely compensated for by the color property correction of the color filter per se (for example, colored layer). This is suitable for preventing a deterioration in color properties of the color filter per se.